The state-run Japan Oil, Gas and Metals National Corporation
(Jogmec) made the announcement 11 March, revealing that a year-long
expedition to the watery depths had finally paid off.

"It is the world's first offshore experiment producing gas from
methane hydrate," an economy, trade and industry ministry official
said to AFP, though other
tests have been carried out before. Jogmec began drilling the
seabed in January, and has just begun a so far successful two-week
long extraction and production experiment to prove that the tricky
substance's potential can be tapped into. The methane hydrate has
been extracted from depths of about 300 metres below the seabed,
with the team lowering the naturally high pressure present at those
depths to separate the gas from its icy surrounds. The free gas was
then piped to the surface.

The successful extraction has massive potential for Japan.

It's estimated that 1.1 trillion cubic metres of natural gas are
trapped within the methane hydrate off Shikoku island. To separate
methane from the icy, solid clathrate that forms under the sea is
to release an estimated 11-year's worth of gas supply for Japan,
which has been struggling under the pressure of soaring energy
prices since the 2011 Fukushima disaster. After the event, most of
the nation's nuclear reactors were forced to shutdown until July
2012. Public support for the nuclear power sector plummeted in the
interim, and the government made the announcement in September 2012
that it would shift to other fuel sources by 2040, closing all 50 functioning
nuclear reactors. But what it intended on replacing that energy
source with remained vague.

Until March 2011, a third of Japan's energy supply came from its
nuclear reactors -- only two of which are now currently in
operation -- and it had planned to increase that ratio to 50
percent. Its reliance on importing gas since the 2011 meltdown has
been a financial strain; it is already the world's largest buyer of
liquid natural gas and the second largest importer of coal. A few
weeks ago, Prime Minister Shinzo Abe appealed to Obama to allow exports of its shale gas to the
fuel-hungry country. So turning methane hydrate extraction into a
viable business could mean independence for Japan -- "Japan could
finally have an energy source to call its own," Takami Kawamoto of
Jogmec said. But why then, hasn't anyone done it before?

Methane hydrate was first discovered in the 1800s, and by the
30s it was still known only as that annoying ice that clogs up
pipelines in the cold. It was only when the substance was
discovered to occur naturally in Siberia that energy scientsits
realised it was not something to consider an irritant, but an
opportunity. Large deposits have since been found in Alaska, Canada
and the Nankai Trough off Japan. According to William Dillon of the
US Geological Survey organic carbon present in gas hydrates is
about twice as much as in all other fossil fuels, and the methane
present is 3,000
times as much as is in the atmosphere (one cubic metre of
methane hydrate equals about 160 to 170 cubic metres of gas).

But conducting extraction experiments on a substance that
resides a kilometre below sea level was never going to be easy.
Once there, deposits are still usually uncovered hundreds of metres
below the seabed and found in areas where the seabed begins to
drop away from the shelf, making it difficult to line pipes up.
Making matters more difficult is the fact that the methane has to
be separated from the clathrate at the point of extraction --
otherwise, the gas is likely to escape when brought to the surface
as the pressure changes.

Jogmec also needs to confirm it can achieve stable extraction,
not just production. Removing large surface areas from the seabed
could cause a shift in sediments where the substance is trapped.
The worse case scenario would be if removal caused an underwater
landslide that triggered a tsunami. In a piece warning about the dangers of
methane hydrate extraction, professor of civil and environmental
engineering at Lehigh University Tae Sup Yun also warned that accidentally releasing methane into the atmosphere
could be a huge danger, considering its aforementioned
concentration in gas hydrates.

Like any new extraction process, it's likely to take plenty of
time before the full go-ahead is given. Fracking continues to cause controversy but has
been embraced, a fact economy, trade and industry minister
Toshimitsu Motegi pointed to at a press conference. "Shale gas was
considered technologically difficult to extract but is now produced
on a large scale," the New York Times reports him as saying. "By tackling these
challenges one by one, we could soon start tapping the resources
that surround Japan."

Image: Shutterstock

Edited by David Cornish

Comments

No! This stuff needs to be left where it is, unless you want Venus 2.0.

Bernard

Mar 13th 2013

3 cheers to global warming!

Sunil

Mar 14th 2013

Split 50/50 on the subject of methane hydrates in energy production; as a flawed extraction method may significantly contribute to global warming; solar, wind and pumped g.p.e. hydro combined with non toxic cheap reusable batter a energy storage method is my ideal future. Ongoing innovations in re-renewable sources point too novel new designs and ideas; for example creating a cyclone with excess heat in order to drive a turbine to generate electricity.

Mike F

Mar 14th 2013

In reply to Mike F

The only problem is that solar, wind, and pumped or battery storage will be something like > £200 / MWh; about 40% of that will be for generation, another 20% for the long-distance connections and balancing, and a truly outrageous 40% for the storage (and only if you get the pumped batteries scaled up and economical - and thats in a country like Japan were you have lots of great hydro options). Gas from hydrates will come in at ~£60MWh. See the problem?